qls,
you said "originally we were discussing hd 7990 performance over gtx 970. not much of a comparison. "
I don't know what that means since some people were all for it and some dead against it. And if I understand correctly you think it's a better card?
I don't know what "not much of a comparison" is supposed to mean either since the raw frame rates are similar in the benchmark. In fact, every card is comparable so it's probably not a term that should be used here.
Anyway, my advice is the GTX970. This model in fact:
http://pcpartpicker.com/part/evga-video-card-04gp42974kr
Update:
By "already a dual-GPU card" I meant you could add another GTX970 later if you needed but that wasn't a good option if you bought the HD7990. That's in response to you stating you were considering Triple Monitor thus needing more performance.
Pricing:
I'm not following you. You said a "faster card for far cheaper"? First of all, it's 9% faster if comparing stock models but if you overclock both cards to max you get nearly IDENTICAL (on average). If you use MFAA on the GTX970 if supported for a game you'll end up with higher on the GTX970.
For $280 it's only about $40 difference between a GTX970 so not sure where "far cheaper" came from.
Let's also not forget that the GTX970 will be far faster in games that have no Crossfire support and that multi-GPU tends to have more stutter so you get overall better SMOOTHNESS on a single-GPU setup.
For $40 more on 970 you get similar raw FPS, smoother gameplay, much quieter card (though you say you don't care) and several features on the GTX970 that the HD7990 does not have.
Anyway, I'm starting to feel like I'm being interrogated more than my help is wanted so I'll bow out...